Pollution-fighting poplar trees

Back in October, I posted about Poplar trees genetically engineered to remove carcinogens from groundwater. The project is moving from the experimental stage into real world application, as described in Fighting pollution the poplar way. The test site was used for oil storage in the 1960s, and became contaminated with trichloroethylene. TCE is an industrial solvent that “has been found in at least 852 of the 1,430 National Priorities List sites identified by the Environmental Protection Agency (EPA) [ATSDR].”
The trees were engineered to over-express the protein cytochrome P450. It is found in most organisms, from plants to people, and functions as a catalyst in many reactions. In laboratory conditions, the transgenic trees were able to remove 91% of TCE from a liquid solution, compared to just 3% removed by untransformed poplars. “The poplar plants — all cuttings just several inches tall growing in vials — also were able to break down, or metabolize, the pollutant into harmless byproducts at rates 100 times that of the control plants [SD].” The plants are able to detoxify a range of chemicals, including chloroform and benzene. The trees can remove chemicals from the air as well as from soil and water.
One benefit of using poplar trees over other plants is that they grow in a wide variety of climates. Another benefit is that they take five years to reach sexual maturity. As long as the trees are harvested before they start producing pollen, the transgenes can not spread to native poplars. These researchers plan to harvest the trees after three years, time that should be adequate to clean up the site. The group is also researching the use of poplars for ethanol, ensuring that the plants will be put to further good use.